1. Technical Field
The present disclosure relates to a converter. More particularly, the present disclosure relates to a converter having a slope compensation circuit.
2. Description of Related Art
With fast developments of power electronics technology, switched-mode converters have been widely used in various applications. In the mean time, there have been increasing demands for converters with better performance. Among control techniques for converters, digital control techniques are easy to be realized in advanced control designs and adaptive to various control topologies, and thus the digital control techniques can improve control operations of the converters, reduce the number of elements in circuit designs, shrink layout areas of control circuits, and enhance reliabilities of the converters.
Among the digital control techniques, the operation of peak-current mode control has advantages such as improving dynamic characteristics and preventing over-current in the converters and also can be utilized to avoid transformer saturation in bridge converters and push-pull converters, and thus it has been widely used in switched-mode converters. However, the operation of the peak-current mode control suffers from the existence of sub-harmonic oscillations, and a slope compensation is introduced into the peak-current mode control in order to reduce the sub-harmonic oscillations.
In conventional digital control operation, there is a digital controller configured for controlling the converter, and the digital controller includes a digital-to-analog converter (DAC) with slope compensation function. However, since the slope compensation in the DAC is implemented with a slope compensation signal having a staircase waveform, the slope compensation signal having the staircase waveform for the control operation of the converter reduces the stabilization and reliability of whole system.